1. Field of the Invention
The invention concerns a data transportation protocol for a wireless network.
2. Description of Related Art
Mobile devices with large storage capacity such as mobile computing devices, image capturing devices, and portable media player devices are becoming more prevalent. It is expected that wireless components such as IEEE 802.11a/b/g or Ultra Wideband (UWB) will be integrated with these mobile devices to provide high bandwidth data access and data sharing abilities. However, existing storage transportation protocols such as IP-based storage protocols (iSCSI, FCIP, iFCP) are not well suited for transporting storage commands and data over a wireless network. These protocols tend to be heavy protocols and are not optimized to appropriately deal with the high packet errors and high packet loss environment of a wireless network. In a wireless network, severe performance degradation of these protocols is encountered.
Typically, a mobile storage device provides a data sharing service that is file based or block based. File based data sharing services include NFS, FTP, CIFS. File based data sharing services suffer from excessive file operation and TCP/IP overhead on the server side.
Block based data sharing services include Internet Small Computer Systems Interface (iSCSI). Block based data sharing services alleviate the burden on the server by moving the file operation to be performed by the client. However, iSCSI is ill suited for wireless networks as it suffers performance degradation due to high bit error and packet loss rates. As most wireless networks are single hop, using the TCP/IP protocol stack is inefficient as there is significant overhead. One solution has been to offload TCP/IP processing to a TCP/IP offload engine (TOE) on a chip or Host Bus Adapter (HBA) In addition to TCP/IP offloading, the encoding and decoding of iSCSI protocol data units (PDUs) can be offloaded to a dedicated iSCSI offload engine to further enhance the performance of the host system. This adds to the total cost of ownership and requires purchase of specialized hardware devices.
Accordingly, there is a desire for an improved transportation protocol for wireless applications. In particular, there is a desire for a transportation protocol highly suitable for short range wireless applications.